x86: Move some variable declarations below the appropriat #ifdef.

This avoids some unused variable warnings with YASM disabled.

libavcodec/x86/ac3dsp_mmx.c

@@ -50,9 +50,9 @@ extern void ff_ac3_extract_exponents_ssse3(uint8_t *exp, int32_t *coef, int nb_c
 
 av_cold void ff_ac3dsp_init_x86(AC3DSPContext *c, int bit_exact)
 {
+#if HAVE_YASM
     int mm_flags = av_get_cpu_flags();
 
-#if HAVE_YASM
     if (mm_flags & AV_CPU_FLAG_MMX) {
         c->ac3_exponent_min = ff_ac3_exponent_min_mmx;
         c->ac3_max_msb_abs_int16 = ff_ac3_max_msb_abs_int16_mmx;

libavcodec/x86/h264_intrapred_init.c

@@ -169,9 +169,9 @@ void ff_pred4x4_vertical_vp8_mmxext(uint8_t *src, const uint8_t *topright, int s
 
 void ff_h264_pred_init_x86(H264PredContext *h, int codec_id, const int bit_depth)
 {
+#if HAVE_YASM
     int mm_flags = av_get_cpu_flags();
 
-#if HAVE_YASM
     if (bit_depth == 8) {
         if (mm_flags & AV_CPU_FLAG_MMX) {
             h->pred16x16[VERT_PRED8x8         ] = ff_pred16x16_vertical_mmx;

libavcodec/x86/vp8dsp-init.c

@@ -283,9 +283,9 @@ DECLARE_LOOP_FILTER(sse4)
 
 av_cold void ff_vp8dsp_init_x86(VP8DSPContext* c)
 {
+#if HAVE_YASM
     int mm_flags = av_get_cpu_flags();
 
-#if HAVE_YASM
     if (mm_flags & AV_CPU_FLAG_MMX) {
         c->vp8_idct_dc_add    = ff_vp8_idct_dc_add_mmx;
         c->vp8_idct_dc_add4y  = ff_vp8_idct_dc_add4y_mmx;